1. Field of the Invention
The invention relates to visual display apparatus of the type used to display input to and/or output from electronic devices such as computers, computer terminals, electronic test equipment, or electronic typewriters. More specifically, the invention relates to visual display apparatus which is easily detachable from the apparatus for which it serves as a display.
2. Description of the Prior Art
The display apparatus generally used with electronic devices such as computers or terminals has as its display element a cathode ray tube (CRT). CRT displays are cheap, trouble-free, and provide a high-quality display. However, in portable electronic devices, the display apparatus generally employs a LCD display as its display element. LCD displays are generally more expensive than CRT displays and provide a lower-quality display, but these disadvantages are overcome by the fact that they have lower power consumption, are much less bulky, and are more resistant to shock and vibration than CRT displays.
The low quality of the display remains a drawback of the portable electronic device, particularly, when, as is often the case, the portable electronic device is used in an environment such as an office where the portable electronic device may be plugged in and where a CRT display is available. In order to permit the use of a higher-quality display apparatus where possible, some manufacturers of portable electronic devices have provided a jack which receives a plug from a CRT display. When the CRT display is available, the user can plug it into the jack and use it instead of the LCD display.
Since the LCD display is not needed when the CRT display is being used and indeed often gets in the user's way when he is using the CRT display, some manufacturers of portable electronic devices have also provided LCD displays which are easily removable from the portable computer. An example of such a prior-art portable electronic device is the Visual Commuter portable computer, manufactured by Visual Computer, Inc. The Visual Commuter's LCD display is physically attached to the CPU case by means of a screw lock connector, and there is a separate cable which plugs into a jack in the CPU case and which provides the electrical connections between the LCD display and the CPU. Removing the LCD display thus involves two operations: unplugging the cable and then physically detaching the LDC display from the CPU case. Reattaching the LCD display is of course the reverse of removing it.
While the detachable LCD displays of the prior art are serviceable, they are unnecessarily difficult to use. The physical and electrical disconnection or connection of the LCD display to the remainder of the apparatus it is used with are separate operations and the physical connection is unnecessarily cumbersome. The invention described herein solves the above problems of the prior art by providing a detachable display apparatus in which physical and electrical connections are made in a single easy operation.